Fluid pressure-actuated apparatus



` March 19, 1957 R. L. ALcoRN, JR 2,785,535

FLUID PRESSURE-ACTUATED APPARATUS Filed July 27, 1955 3 Sheets-Sheet lwww March 19, 1957 Filed July 27, 1953 R. L. ALCORN, JR

FLUID PRESSURE-ACTUATED APPARATUS '3 Sheets-Sheet 2 OR/FICE March 19,1957 R. L. ALCORN, JR

FLUID PRESSURE-ACTUATED APPARATUS 3 Sheets-Sheet 3 Filed July 27, 1953United States Patent O FLUID PRESSURE-ACTUATED APPARATUS Robert L.Alcorn, Sir., Chambersburg, Pa., assignor to Chambersburg EngineeringCompany, Chambersburg, Pa., a corporation of Pennsylvania ApplicationJuly 27, 1953, Serial No. 370,364

7 Claims. (Cl. 60-97) This invention relates to fluid pressure-actuateddevices in which there is at least one movable member that is movedthrough a work stroke and through a return stroke. An example of such adevice is a forging apparatus in which a forging member is driven athigh velocity against a work piece to be forged. One form of suchapparatus that is now in use comprises two forging rams or impactersarranged horizontally in opposing relation to each other and which areoperated very rapidly to forge successive work pieces that are fed tothe apparatus. Such an apparatus is disclosed in U. S. Patent No.2,615,306, issued October 28, 1952, to R. L. Alcorn, Jr., and assignedto the assignee of the present applica- Ition.

It is desirable to be able to move the work-performing member or membersin such an apparatus slowly for inspection or checking, but it isusually impractical to move the work-performing member by hand. ln adouble impacter apparatus such as above-mentioned7 for example, it issometimes desired to check the dies for die setting, but this has beenvery difficult in the past due to difficulty in moving the impactersexcept in their usual high velocity operation.

One object of the present invention is to provide, in an apparatus ofthe general character above-mentioned, an arrangement whereby theWork-performing member or members can be moved slowly, i. e. inched orjogged, whenever desired to enable checking or inspection.

Another object of the invention is to provide such an apparatus which iseasily operable by the operator, and which aifords complete safety tothe operator.

A more speciic object of the invention is to provide such an arrangementin a double impacter forging apparatus of the character disclosed in theabove-mentioned patent.

Other objects and features of the invention will be apparent from thefollowing detailed description.

While the inveniton contemplates the provision of an inching or joggingarrangement in any apparatus of the general character above-mentioned,it will be described herein with specic reference to its embodiment in adouble, impacter forging apparatus of the character disclosed in theabove-mentioned patent, especially since a specific object of theinvention is to provide inching or jogging control in that apparatus.

ln the accompanying drawings,

Fig. l is a front elevational view of a double impacter forgingapparatus to which the present invention is applied;

Fig. 2 is a diagrammatic illustration of the control arrangementemployed in the apparatus;

Fig. 3 is a detailed illustration of the control arrangement; and

Fig. 4 is a diagrammatic illustration of the electrical system employed.

Referring rst to Fig. 1, the illustrated apparatus comprises asupporting frame on which are mounted two horizontally aligned uidcylinders 11 and 11a within which there are movable rams or impacters 12and 12a to which the forging dies 13 and 13a are removably attached. Inthe illustration the impacters and their dies are shown in theirinnermost positions Without a work piece interposed, the dies being inabutting relation to one another. rlhis is the condition of the movableparts for inspection when the apparatus is now in operation. lt will beunderstood that during forging operation of the apparatus the dies 1 3and 13a engage a work piece to forge the same to a desired shape.

For the purpose of the present application, it is only necessary to givea general description of the apparatus preparatory to a description ofthe present invention. Referring still to Fig. 1, during forgingoperation of the apparatus pressurized lluid, which is preferablycompressed air, is supplied to the outer ends of the cylinders to drivethe rams or impacters through their Work stroke. Immediately followingthe forging of a work piece the rams or impacters are moved throughtheir return stroke by admitting pressurized iluid to the inner ends ofthe cylinders, and at the same time the previously admitted duid isexhausted from the cylinders.

Figs. 2 and 3 show the fluid control system by which the rams orimpacters are actuated. Fig. 2 is a generalzed illustration of thecomplete system, While Fig. 3 is a detailed illustration showing howeach ram or impacter is actuated. Referring particularly to Fig. 3, thepressurized uid to operate the ram or impacter 12 through its workstroke is introduced to the pressure end of cylinder l1 from conduit 14through chamber 15 and port 16 when valve 17 is open and valve 18 isclosed. Pressurized uid to actuate the ram or impacter 12 through itsreturn stroke is introduced through conduit i9 to the return end of thecylinder 11, and during the return stroke valve 17 is closed and valve18 is open as shown, to exhaust the previously admitted fluid throughexhaust port 2G. Valves 17 and 1S are actuated by pressurized fluidunder control of a solenoid-operated valve 21. A secondsolenoid-operated valve 22 serves to control the admission of fluidpressure to the return end of cylinder 11, and also to control theexhaust of such fluid. The solenoids 23 and 2d for operating the valves21 and 22 are controlled by cyclic control apparatus represented inblock form at 25, which apparatus may be of the character disclosed inFig. 6 of the above-mentioned patent. Since the present invention is notconcerned with the details of the cyclic control apparatus, there is noneed to illustrate or describe the same. It suffices to note that thisapparatus effects cyclic energization and deenergization of thesolenoids as hereinafter mentioned.

The apparatus is shown `at the end of an operating cycle just prior tothe opening of valve 17 and the closing of valve 18 to initiate a newoperating cycle. Solenoid Z3 is deenergized, and under the influence ofthe biasing spring 26 the movable valve member 27 is in the positionshown, and pressurized fluid is being supplied through conduit 2S,conduit 29, differential controlling valve 3d and conduit 3i to thepilot valve )i7 which is maintained closed by the applied pressurizedhuid. At the same time pressurized fluid is supplied through conduit 31ato the pilot valve of the other cylinder corresponding to the pilotvalve 17. The differential controlling valve 30 cnables differentialcontrol of the fluid supply to the inlet pilot valves of the twocylinders, as described in the above-mentioned patent. Conduit 32, whichconnects with conduits 3? and 33a, is in communication with the exhaustconduit 3d of the valve 21 and, therefore, valve 118 and thecorresponding valve of the other cylinder are open. Solenoid 24 is alsodeenergized, and movable valve member 3S is in the position shown underthe inliuence of the biasing spring 36. Conduit 37, which connects withconduits 19 and 19a, is in communication With exhaust conduit 38.

Energization of solenoid 23 causes movement of valve member 27 to theright, placing conduit 32 in communication with the fluid supply conduit28 and thus causes closure of valve 18 and the corresponding valve ofthe other cylinder. At the same time conduit 29 is placed incommunication with exhaust conduit 39, causing opening of valve 17 andthe corresponding valve of the other cylinder. At this time pressurizedfluid is supplied to the cylinders to drive the impacters through theirwork stroke. At the end of the Work stroke solenoid 23 is deenergizedand solenoid 24 is energized. The deenergiza ion :of ysolenoid Z3 causesclosure of valve l7 and opening of valve i8, and correspondiny operationof the valves of the other cylinder. The energization of solenoid 24causes valve member 35 to mov-e to the right, thereby placing conduit 37in communication with uid supply conduit 4d. Pressurized fluid is thensupplied to the cylinders through conduits 19 and 19a to drive theimpacters through their return stroke. Solenoid Z4 is then deenergizedand the movable elements are again positioned as shown in Fig. 3, forstart of the next oper-ating cycle.

In order to cushion the impacters at the end of their return stroke, ranarrangement is provided at each cylinder as now to be described, and aswiil be seen later this same arrangement is conveniently used for thepurpose of the present invention. Referring still to Fig, 3, it will benoted that the port i6 is located in spaced relation to the associatedend of the cylinder l1, and a by-pass port 4l extends from the end ofthe cylinder and communicates with chamber l upon opening of aspring-biased valve 42 who-se biasing spring 43 ytends to maintain theValve closed. At the end of the `return stroke of the impacter 11.2,some of the pressurized fluid is trapped at the lefthand end of thecylinder and serves to cushion the impacter. At the start of the neXtoperating cycle, the operating fluid. entering from conduit i4 forcesvalve 42 open and enough duid is admitted through port 41 to move theimpacter sufficiently to uncover the main port i6.

As thus far described, the apparatus is similar in structure andoperation to that disclosed in the above-mentioned patent. 1n accordancewith the present invention, an .arrangement now to be described isprovided in association with each cylinder to enable inching or joggingmovement of the impacters, and at the saine time prevent the apparatusfrom going through its cycle or forging operation.

As may be seen in Figs'. 2 and 3, solenoid-operated valves 44 and 44aare utilized to effect the inching or jogging operation. Referringparticularly to Fig. 3, valve 44 is typical and is connected by conduit45 to the chamber of valve 42 and thence to port 41. When the solenoid46 is deenergized, the movable valve member 47 is in the position shownunder the inuence of the biasing spring 48. In this position of thevalve member 47, the inlet end of conduit 45 is closed. However,energization of solenoid 46 causes upward movement of valve member 47 toplace conduit 45 in communication with a pressurized fluid supplyconduit 49. This effects supply of pressurized fluid to the end ofcylinder 11 through conduit 45 and port 41, but the quantity or volumeof fluid flow is relatively low so as to exert relatively small force onthe impacter 12 to move it slowly toward -the right. An orifice 50 isprovided in conduit 45 to limit the volume of the fluid flow. The mannerin which solenoid 46 is controlled will be described later.

As further shown in Figs. 2 and 3, the main fluid supply conduits l4 and14a are connected `to spring-biased pressurenesponsive valves 51 and51a. Valve 51 is typical, and as shown in Fig. 3 its movable valvemember` is urged by the biasing sp-ring 52 into engagement with thevalve seat. Conduits 53 and 53a connect the chambers of valves 5l and51a with the chamber of a valve 54 through which the pressurized duid issupplied by conduit 55, the latter being connected to the pressurizedduid source. The movable valve member 56 is pivotally CII connected toone end of a link 57 whose opposite end is pivotally connected to amanually-operable lever 58. The lever 58 has one end pivotally fulcrumedat 59 on a stationary bracket 60 mounted on the casing of valve 54.Lever 58 is weighted at 6l to urge the movable valve member 56 downwardto the position shown. Link 57 has a recess or notch 62 therein which isengageable by the nose 63 of a latch element 64 pivoted at 65 on thevalve casing. A tension spring 66 is interconnected between the latchelement 64 and bracket 6&9 so as to urge the latch clement 64 toineffective position. The latch element 64 is connected by a link 67 tothe armature 68 of a solenoid 69, whereby energization of the solenoid69 moves the latch element 64 to effective position and maintains it inthat position. It will be seen, therefore, lthat if solenoid 69 isenergized and if the lever 55 is manually raised, the movable valvemember 56 is latched in raised position.

The lowered position Iof valve member 56, as shown, is the position forinching or jogging operation as hereinafter described. In this positionof the valve member 56, 4the inlet port 7d of valve 54 is cut o from theoutlet port 7l, so that the pressurized fluid supply .conduit 55 iseffectively closed. At the same time the port 71 is in communicationwith an exhaust port 72. The pu-rpose of .this is to exhaust pressurefrom the conduits 53 and 53a, the reason for which will be made clear inthe subsequent description of the operation.

During the forging operation, the valve member 56 is in raised position,being held in `that position in the manner above-described. With thevalve member raised the inlet port 70 is in communication wit-h the`outlet port 7l, `and the exhaust port 72 is closed. Consequently,pressurized fluid is supplied to con-duits S3 and 53a, and the pressurein these conduits holds valves 5l and 51a open. The reason for providing.these valves will be made clear in the subsequent description of theoperation.

Referring now to Fig. 4, ythere is shown the electrical system by whichthe electrically operated elements are controlled to effect the inchingor jogging operation. The solenoids 23 and 24, which are connected tothe cyclic control apparatus 25 for effecting the cyclic forgingoperation, are also included in the control cir-cuits for the inching orjogging operation. A two-position manual switch 73, which may be atoggle switch, is set in one position for forging operation of theapparatus and is set in the other position for inching or joggingcontrol. This switch has two movable contacts 74 and 75 which aremechanically interconnected. It is shown in the position for the forgingoperation, in which position it serves to maintain relay 76 energized.This relay is initially energized by momentary 4closure of a resetswitch 77 which is `biased to open position, and the relay locks itselfin through contact 7S. With the relay energized, solenoid 69 isenergized through contact 79 .and holds valve 54 open asabove-described.

When it is desired to eiect inching or jogging operation, the cycliccontrol apparatus 25 is turned off and switch 73 is moved to its otherposition in which contact 74 is opened and contact 75 is closed. Theopening of contact 74 causes deenergization of relay 76, whereupon relaycontacts 78 and 79 open and Contact 80 closes. The opening of contact 79deenergizes solenoid 69, whereupon the valve 54 (Fig. 3) closes underthe influence of weight 61, thereby shutting off the main uid supplyline. Remembering that contacts 75 and 80 are now closed, inching orjogging of either the right-hand impacter or the left-hand impacter maybe eifectedby closure of switch 81 or S2. These switches are both dualcontact switches, switch 81 comprising mechanically interconnectedcontacts 83 and 84, and switch 82 comprising interconnected contacts 85and 86. Both of the switches 81 and 82 are biased to the open positionas by means of springs (not shown).

Y Closure of switch S1 energizes solenoids 23 and 46. As previouslydescribed, and as may be seen in Fig. 3,

the energization of solenoid 23 effects opening of inlet valve 17 andclosure of exhaust valve 18, while cnergization of solenoid 46 causesintroduction of pressurized fluid through conduit 45, Linder control oforifice 50, to effect slow movement of the impacter 12. This pressurizedfluid enters the cylinder 11 through port 41, and as the impacter 1,2moves toward the right it uncovers port 16. Some of the pressurizedfluid, therefore, flows through port 16 into chamber 15, and since valve17 is open, it also flows into conduit 14 but is trapped by valve 51.This valve is closed under the influence of its spring, it beingremembered that the pressure in conduit 53 has been exhausted throughexhaust port 72 of valve 54.

The reasons for exhausting the pressure from conduits 53 and 53a and forproviding the valves 51 and 51a may now be appreciated, Referring toconduit 53, for example, if the pressure therein were not exhaustedpreparatory to the inching or jogging operation there might besuflicient pressure remaining in this conduit to drive the impacter 12forwardly at high velocity upon initial opening of the inlet valve 17 atthe start of the inching operation. Exhausting the pressure from conduit53 before commencement of the inching operation prevents thisundesirable action from taking place. With the conduit 53 incommunication with the exhaust port 72, the spring-closed valve 51prevents pressurized fluid from flowing into the conduit 53 during theinching operation. As above-described, the pressurized fluid introducedduring inching fills port 16 chamber 15 and conduit 14, but is trappedby the valve 51. Were it not for this valve the pressurized fluid couldflow through conduit 53 and out through exhaust port 72, which wouldtend to defeat the inching operation.

Referring again to Fig. 4, closure of switch 32 effects energization ofsolenoid 23 and solenoid 46a, the latter corresponding to solenoid 46and serving to control admission of pressurized fluid to the othercylinder 11a to effect slow movement of the other impacter 12a. Theinching operation of the other impacter is the same as described above.

From the above description it will be seen that the manual switches 81and 82 serve to control the inching operations of the respectiveimpacters 12 and 12a. By operation of these switches the two impactersmay be brought slowly to their meeting position as shown in Fig. 1.

Switch 87 is for the purpose of effecting return movement of theimpacters. This switch comprises mechanically interconnected contacts 88and 59 which are biased to the positions shown. Operation of the switcheffects opening of Contact 8S to render the jogging circuits inoperativeand edects closing of contacts $9 to energize the solenoid 24. Theenergization of solenoid 24, as may be seen in Fig. 3, effects returnmovement of the impacters just as it does during the cyclic forgingoperation. Since solenoid 23 is now deenergized, the exhaust valve 18 isopen to exhaust the previously admitted fluid.

Resumption of the forging operation of the apparatus is effected byreturning switch 73 to the position shown, then momentarily closingswitch 77 to energize relay 76 and thus energize solenoid 69, thenmanually raising lever S to effect latching of valve member 56 in openposition, and finally starting the cyclic control apparatus 25. ltshould be noted that resumption of automatic operation cannot take placeuntil the operator has raised the manual lever 53. This is an importantsafety feature, as it insures against accidental starting of theautomatic operation if the cyclic control apparatus 25 is startedinadvertently, which might otherwise cause injury to a person inspectingor replacing the dies.

While a particular embodiment of the invention has been illustrated anddescribed, the invention is not limited thereto, but contemplates suchother embodiments or modifications as may occur to those skilled in theart.

I claim:

l. In combination, a fluid cylinder, a piston in said cylinder movablethrough a work stroke and a return stroke, a first conduit means forsupplying pressurized fluid at high velocity to said cylinder so as todrive said piston through its work stroke, a second conduit means forsupplying pressurized fluid to said cylinder so as to return the piston,means for controlling the flow of fluid in said first and second conduitmeans so as to effect repeated operation of said piston, a third conduitmeans for supplying pressurized fluid at low velocity to said cylinderso as to move the piston slowly in the direction of its work stroke, avalve in said first conduit means biased toward closed position,normally-energized electrical means arranged to hold said valve in openposition, a valve in said third conduit means biased to closed position,normally-deenergized electrical means arranged to open said last valve,means operable at will to deenergize said first electrical means andthus close said first valve, and means operable at will to energize saidlast electrical means and thus open said last valve to effect slowmovement of said piston.

2. In combination, a fluid cylinder, a piston in said cylinder movablethrough a work stroke and. a return stroke, a first conduit means forsupplying pressurized fluid at high velocity to said cylinder so as todrive said piston through its work stroke, a second conduit means forsupplying pressurized fluid to Said cylinder so as to return the piston,means for controlling the flow of fluid in said first and second conduitmeans so as to effect repeated operation of said piston, a third conduitmeans for supplying pressurized fluid at low velocity to said cylinderso as to move the piston slowly in the direction of its work stroke, avalve in said first conduit means biased toward closed position, anormally-energized solenoid, latch means actuated by said solenoid tohold said valve normally in open position, a valve in said third conduitmeans biased to closed position, a normally-deenergized solenoidarranged to open said last valve, means operable at will to deenergizesaid first solenoid and thus close said first valve, and means operableat will to energize said last solenoid and thus open said last valve toeffect slow movement of said piston.

3. In combination, aV pair of horizontally aligned cylinders, a pair ofopposed pistons in said cylinders movable toward one another in a workstroke and movable away from one another in a return stroke, a firstconduit means for supplying pressurized fluid at high velocity to eachof said cylinders so as to drive said pistons toward one another, asecond conduit means for supplying pressurized fluid to each of saidcylinders so as to return the pistons, means for controlling the flow offluid in said rst and second conduit means so as to effect repeatedoperation of said pistons, a third conduit means for supplyingpressurized fluid at low velocity to each of said cylinders so as tomove the pistons slowly toward one another, valve means in said firstconduit means biased toward closed position, a normally-energizedsolenoid, latch means actuated by said solenoid to hold said valve meansin open position, valve means in said third conduit means biased toclosed position, a normally-deenergized solenoid arranged to open saidlast valve means, means operable at will to deenergize said firstsolenoid and thus close said first valve means, and means operable atwill to energize said last solenoid and thus open said last valve meansto effect slow movement of said pistons toward one another.

4. In combination, a fluid cylinder, a piston in said cylinder movablethrough a work stroke and a return stroke, a first conduit means forsupplying pressurized fluid at high velocity to said cylinder so as todrive said piston through its work stroke, a second conduit means forsupplying pressurized fluid to said cylinder so as to return the piston,means for controlling the flow of fluid in said first and second conduitmeans so as to effect repeated operation of said piston, a third conduitmeans for supplying pressurized fiuid at low velocity to said cylinderso as to move the piston slowly in the direction of its work stroke, avalve in said first conduit means biased toward closed position butmanually movable to open position, latch means for holding said valve inopen position, a valve in said third `conduit means biased to closedposition, means operable at will to release Said latch means and therebyeffect closure of said first valve, and means operable at will to opensaid last Valve to effect slow movement of said piston.

5. In combination, a fluid cylinder, a piston in said cylinder movablethrough a work stroke and a return stroke, input and exhaust valvesoperatively connected to one end of said cylinder, conduit means forsupplying pressurized fiuid at high velocity to the said end of saidcylinder under control of the input valve, means including a solenoidfor actuating said valves, means including another valve and anoperating solenoid therefor for supplying pressurized fluid to the otherend of said cylinder so as to return the piston, conduit means forsupplying pressurized fluid at low velocity to the first end of saidcylinder so as to move the piston slowly in the direction of its workstroke, a normally-open valve in said first conduit means to enableclosure thereof, a solenoidoperated normally-closed valve in said lastconduit means, manual-switch-controlled circuit meansffor energizingsaid first so-lenoid and the operating solenoid of said last Valve toefi'ect slow movement of said piston in the direction of its workstroke, circuit means for energizing said second solenoid, and manualswitch means for simultaneously opening said first circuit means andclosing said last circuit means to effect return of the piston.

6. In combination, a fluid cylinder, a piston in said cylinder movablethrough a work stroke and a return stroke, input and exhaust valvesoperatively connected to one end of said cylinder, conduit means forsupplying pressurized fiuid at high velocity to the said end of saidcylinder under control of the input valve, means including a solenoidfor actuating said valves, means including another valve and anoperating solenoid therefor for supplying pressurized fluid to the otherend `of said cylinder so as to return the piston, cyclically-operablemeans for effecting timed intermittent energization of said solenoids soas to eect automatic repeated operation of said piston and adapted to berendered inoperative at will, conduit means for supplying pressurizedfluid at low velocity to the first end of said cylinder so as to movethe piston slowly in the direction of its work stroke, a normallyopenvalve in said first conduit means to enable closure thereof, asolenoid-operated normally-closed valve in said last conduit means,manual-sWitch-controlled circuit means for energizing said firstsolenoid and the operating solenoid of said last Valve to effect slowmovement of said piston in the direction of its work stroke, circuitmeans for energizing said second solenoid, and manual switch means forsimultaneously opening said first circuit means and closing said lastcircuit means to effect return of the piston.

7. In combination, a fluid cylinder, a piston in said cylinder movablethrough a work stroke and a return stroke, a first conduit means forsupplying pressurized fluid at high velocity to said cylinder so as todrive said piston through its work stroke, a second conduit means forsupplying pressurized fluid to said cylinder so as to return the piston,means for controlling the ow of uid in said first and second conduitmeans so as to effect repeated operation of said piston, a third conduitmeans for supplying pressurized fiuid at low velocity to said cylinderso as to move the piston slowly in the direction of its Work stroke, anormally open valve in said rst conduit means, a valve in said firstconduit means between said first valve and said cylinder, spring biasedto closed position when said rst valve is closed and opened by fluidpressure when said first valve is open, a normally closed valve in saidthird conduit means and means operable at will to close said first valveand open said second valve to effect slow movement of said piston.

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